if __name__ == '__main__':
    # x = 5
    # print(id(x))
    # for i in range(20):
    #     print(id(i))

    # 赋值操作在 Python 中是关联操作
    x = 5
    print(id(x))
    # 将 y 关联到 x，结果就是 xy 同时关联到 5
    y = x
    print(id(y))

    def show_addr(num):
        print(id(num))

    show_addr(x)
